During a trip to survey booming oil development in North Dakota, Interior Secretary Sally Jewell said she saw evidence that energy companies are working aggressively to pare greenhouse gas emissions ahead of federal regulations.

During her two-day visit to North Dakota, Jewell visited an oil rig working for Oklahoma City-based Continental Resources, a major operator in the Bakken and Three Forks plays of Montana and North Dakota. She also toured facilities operated by Norway's Statoil, which has invested more than $4 billion in the region.

It was Jewell's first visit to the surging oil region since she became interior secretary in April.

“It's extraordinary how much oil is in the ground here and is being produced,” she said in an interview. “North Dakota has become the second-largest producer of crude oil among the 50 states. It has passed Alaska. It has passed California.”

“To see that on the ground is amazing,” Jewell added.

Despite the flurry of activity — which has turned Williston, N.D., into a boomtown — Jewell said oil and gas infrastructure hasn't taken over the area. By drawing on horizontal drilling techniques, oil companies are able to drill lateral wells that stretch far beyond the well pad. As a result, Jewell said, “the footprint on the ground is less dramatic than you might expect.”

Statoil workers highlighted a pilot project to capture natural gas as a compressed liquid and then put it to use fueling rigs and other equipment, effectively slashing the use of diesel in the oil field. The company also is working on gas lift projects, where natural gas is pumped back into wells to aid overall production.

“There's no question that these guys are working to try and address the carbon pollution issue and the methane release,” Jewell said.

Hoeven cast the projects as evidence of “the progress we've made by deploying new technologies that are producing more energy with better environmental stewardship.”

Such innovations may be key for oil companies to find beneficial and commercial uses for the natural gas they bring up along with the crude, instead of burning off the hydrocarbon.

Conservationists say natural gas flaring and venting hurts the environment, while depriving taxpayers of revenue that would be tied to selling the fossil fuel. Although methane does not remain in the atmosphere as long as other greenhouse gases, it is 21 times more potent than carbon dioxide when it comes to warming the atmosphere.

The Obama administration is taking aim at the practice. As part of a plan for combating climate change unveiled in June, President Barack Obama pledged to pare methane emissions tied to natural gas, both at the wellhead and when the fossil fuel is transmitted.

Obama directed executive agencies to develop a comprehensive strategy for tackling methane emissions, including support for efforts to build and upgrade gas pipelines.